Skateboarding is a popular sport and for some is even a means of transportation. One typical problem a skateboarder encounters is the need to propel the skateboard forward for example, when the slope of the terrain is too shallow and does not allow gravity to pull the skateboard and rider down the slope. Typically, the skateboarder will place one foot on the skateboard and utilize the other foot to push or propel the skateboard forward. This pushing motion, however, can become tiresome and may detract from the more pleasurable experience of riding the board with both feet on it.
The truck is an important element in the design of skateboards, wheeled platforms, roller skates, inline skates and vehicles. The truck not only supports the wheels of the skateboard, platform, inline skates, roller skates or vehicle, it may also provide the user with a significant degree of directional control.
In a typical skateboard truck, directional control is accomplished by providing the truck with four primary components: a truck hanger, a base plate, a kingpin, and bushings. Typically skateboard trucks (FIGS. 1 and 2) have two (2) axle extensions, which protrude laterally from the sides of the truck hanger upon which the skateboard wheels and bearings are mounted. Skateboard trucks are a wide variety of construction and designs beyond the typical truck described herein. Each of these trucks designs tends to exhibit most, if not all, of the characteristics described below. Skateboard trucks are typically mounted to the skateboard deck in a front (or leading) and rear (or trailing) position along the longitudinal or lengthwise axis of the skateboard deck such that, at rest, the truck axle extensions at the leading position are roughly parallel to the truck axle extensions at the trailing position and all truck axle extensions are roughly perpendicular to the longitudinal axis of the skateboard deck when the skateboard is at rest. If this approximately parallel alignment of the trucks and their respective axles are maintained while the skateboard rolls along the ground, the skateboard's path will be relatively straight.
A skateboard truck typically exhibits some dynamic response when the user of the skateboard or wheeled platform leans to one side or the other. Such dynamic response tends to cause the truck hanger and axles to exhibit a component of rotation, in part, around a vertical axis, or an axis oriented perpendicular to the ground surface upon which the skateboard is positioned. The leading hanger and trailing hanger typically (but not necessarily) rotate in opposite directions. Thus, the user can turn, or otherwise control the forward direction of the wheeled platform, by shifting his or her body from one side of the platform to the other. Bushings are located between the truck base plate and truck hanger in the most common truck design. A kingpin connects the hanger, base plate and bushings together. The threaded kingpin can be tightened and loosened to modify rigidity of the bushings, and the dynamic response characteristics of the truck. Loose or slack bushings generally allow greater movement of the hanger about the kingpin and vertical axis of the truck, and thus are less responsive to slight weight shifts than are tight or rigid bushings.
Most, if not all skateboard truck designs exhibit some undesirable ride characteristics. One such undesired ride characteristic is instability or “speed wobble”, which occurs when the axle and hanger develop a resonant frequency of vibration and uncontrolled wobbling within their typical range of motion. This can cause instability in the user's control of the skateboard, wheeled platform or vehicle. Speed wobbles occur on most skateboard truck designs. Different designs experience these wobbles at different speeds and under different conditions.
In addition, skateboards often do not provide a sensation for the rider that is similar to the gains and losses in speed encountered when turning, curving, and straightening ones path when snowboarding downhill or surfing ocean waves due to the requirement to periodically remove one foot from the board to propel the skateboard. Many geographic areas do not have the terrain required to allow gravity to do some or all the work of propelling the skateboard.
Furthermore, many skateboards suffer from distracting wobbles and vibration at higher rates of speed. Thus, the use of the hydraulic system will tend to dampen the vibrations and provide for a much more stable and controlled feeling for the occupant.
Although, there have been innovations in the self-powered skateboard, none of the innovations have utilized a hydraulic system and method of converting linear motion into rotational motion to propel the skateboard forward.
Accordingly, what is needed is a system and method utilizing a hydraulic system to convert linear motion into rotational motion to propel a skateboard forward and provide a sensation similar to snowboarding or surfing without having to put one foot on the ground to propel the skateboard and without the need for gravity or inclined surfaces.
Furthermore, most common skateboard truck designs do not transfer energy generated by the rider into the rotation of the skateboard wheels, resulting directly in the locomotion of a skateboard, wheeled platform or vehicle. Accordingly, what is needed is an improved truck assembly that can dynamically steer a wheeled platform, substantially reduce the impact of speed wobbles under typical riding conditions, and generate rotational energy to be used to propel the skateboard, wheeled platform, roller skates, inline skates, or vehicle.
Additionally, for maximum transfer of energy from the rider to the rotation of the at least one rotor, axle or wheel, the rider's gravitational, centrifugal and muscular energy should be structurally supported predominantly or entirely by components actively involved in the transfer of energy from the platform to the wheels. Accordingly, what is additionally needed is an entirely new truck design that strives to minimize support structures that are not used directly in the transfer of energy from the rider into the wheels.
Additionally, for maximum velocity potential of a mechanically propelled wheeled platform, what is needed is temporary storage and subsequent delayed release of potential energy. This potential energy is created by the rider's gravitational, centrifugal and muscular energy during a turn and is released into the rotation of the at least one rotor, axle or wheel at a later time. This stored potential energy should be created and stored temporarily when the gravitational, centrifugal, and frictional loading are greatest, which occurs while the turning radius is decreasing. Increased velocity potential is achieved if this stored potential energy is released between turns when the gravitational, centrifugal, and frictional loading is decreased
Additionally, what is needed for maximum dynamic range of steering at all velocities, is the storing and delayed transfer of potential energy from the rider into the rotation of the at least one rotor, axle or wheel. In this wheeled platform, the steering response and the transfer of power from the rider to the mechanical wheeled platform are accomplished by the same action, rotation of the platform of the deck. If the transfer of energy for the propulsion of the wheeled platform is instantaneous (direct-drive), the potential exists for the inhibited response of the steering dynamics. This could be problematic at slower speeds when a huge amount of torque is needed to get the vehicle up to speed. On the other hand, if the energy generated for the propulsion of the wheeled platform is stored temporarily (in a spring, for example) and not delivered instantaneously to the mechanisms which propel the wheeled platform, the steering response does not need to be inhibited by the generation of power.